An inkjet printing system may include a printhead and an ink supply which supplies liquid ink to the printhead. The printhead ejects ink drops through a plurality of orifices or nozzles and toward a print medium, such as a sheet of paper, so as to print onto the print medium. Use of an inkjet printing system generates heat on a printhead. If the heat of a printhead becomes too high, the print quality of an inkjet printing system may degrade and a malfunction of the printhead or other inkjet printing system may occur. The heat may be increased with an increase in a firing frequency of a printhead or an increase in the print density of an image being printed. A reduction of the firing frequency of a printhead may increase the amount of time it takes to complete a print job, and a decrease in the print density of an image being printed may result in a lower print quality.